Winch operated derrick



1955 w. E. SCHWERDTFEGER 3,214,139

WINCH OPERATED DERRI CK Filed March 5, 1962 INVENTOR.

W/LBUR E. SCHWERDTFEGER BY q United States Patent 3,214,139 WINCH OPERATED DERRICK Wilbur E. Schwerdtfeger, Western Springs, 11]., assignor to International Harvester Company, Chicago, 111., a corporation of N ew Jersey Filed Mar. 5, 1962, Ser. No. 177,455 4 Claims. (Cl. 254-145) The present invention relates generally to improvements in derricks and the like and more particularly to new and improved winch operated derricks, wherein said winch includes a friction clutch and brake means.

In the field of derricks it has been the general practice to employ winches to raise and lower the boom of the derrick. Although such devices have served the purpose it is not proved entirely satisfactory in all conditions since the weight of the boom and its load often makes it difficult to lower the boom in a controlled condition. The general purpose of this invention is to provide a winchoperated derrick in which the boom can be lowered under a controlled condition. To obtain this the present invention contemplates providing a friction clutch and brake means in the winch. When lowering the boom with the derrick a braking pressure is applied and thus allows the boom to be lowered at any rate desired. During the lowering operation the operator holds the crank of the winch stationary and thus it is not likely to run away as would the ordinary winch. Since the operator has the winch under control at all times the boom can be stopped at any point desired in its downward motion.

An object of the present invention is to provide an improved winch operated derrick.

A further object of the invention is to provide a winch operated derrick that can be lowered in a controlled condition.

Another object of the invention is to provide a winch operated derrick having a clutch and brake means.

Still another object is to provide an improved winch which includes a friction clutch and brake.

FIGURE 1 shows a side elevator view of the derrick supporting a farm elevator;

FIGURE 2 shows a top plan view of the winch; and

FIGURE 3 shows a section of the winch taken on the lines 3-3 of FIGURE 2 looking in the direction of the arrows.

Referring now to the drawings wherein like reference characters designate like or corresponding parts throughout the several views there is shown in FIGURE 1 a side elevator view of the derrick 6 supporting a farm elevator 5. The derrick comprises a base 7 having a pair of wheels 10 mounted thereon and a pivoted boom 8 extending upwardly from said base. The farm elevator is supported at two points on the derrick, one at a point on the base and the other at the free end of the boom. The free end of boom 8 is permitted to slide along the bottom surface of elevator 5. As the boom is pivoted on the base of the derrick the elevation of the farm elevator is changed. The boom is raised and lowered by a winch 9 which is mounted on the base of the derrick.

Referring now to FIGURES 2 and 3 wherein the winch is shown in detail, it comprises a support 14 which is secured by bolts or other means to the base of the derrick. A pinion shaft 15 having a threaded outer end 16 is rotatably mounted on the support by bearings 17. A first ratchet 18 having a square shape is fixedly carried by the pinion shaft and cooperates with the pawl 19 which is pivotally mounted on the support about pivot 20. As can be seen in FIGURE 3 this ratchet and pawl arrangement will allow pinion shaft 15 to rotate in a clockwise direction but prevent its rotation in the counterclockwise direction. This ratchet and pawl arrangement will also provide step by step rotation of the shaft requiring it to turn of a turn per step. A stationary clutch plate 21 having a friction surface 22 is fixedly secured to said pinion shaft adjacent the ratchet 18. A movable clutch plate 23 having a friction surface 24 is rotatably mounted on the pinion shaft 15. Between the friction surfaces 22 and 24 of the clutch plates is rotatably mounted a pinion sprocket wheel 25. The movable clutch plate and pinion sprocket wheel are held on the pinion shaft by an internally threaded nut 26 having a crank 27 secured thereto. From the above description it can be seen that as nut 26 is tightened on pinion shaft 15 by the crank 27, the pinion sprocket wheel will be frictionally held between the two clutch plates. Upon further rotation of the crank, the pinion sprocket wheel will be rotated with the pinion shaft.

A second shaft 28 is rotatably mounted on the support 14 in a position offset from said first shaft and parallel thereto. A second ratchet 30 is fixedly secured to this shaft and cooperates with a second pawl 31 which is pivoted about a point 22 to the support, This ratchet and pawl arrangement will allow said second shaft, as seen in FIGURE 3, to rotate in a clockwise direction but prevent its counterclockwise rotation. This ratchet and pawl arrangement can be disengaged by raising the pawl to the vertical position as shown in broken lines in FIG- URE 3. With the pawl so disengaged the second shaft can rotate in either direction. A second sprocket wheel 33 is fixedly secured to said second shaft at a point adjacent the pinion sprocket wheel. Also fixedly mounted on said second shaft is a drum 34 which is adapted to contain a cable 36 secured at one end to the drum and wound around it. The other end of said cable is threaded through a pulley 37 secured to the derrick, through a pulley 38 on the free end of the boom 8 and then secured to a fixed member adjacent pulley 37. A chain 35 or other flexible connection means is provided to transmit the rotary motion of the pinion sprocket wheel to the second sprocket wheel.

Operation Assuming that the derrick and farm elevator are in the positions shown in FIGURE 1, and it is desired to raise the upper end of the farm elevator, the operator would merely grasp the crank 27 rotates it in a clockwise direction until the clutch plates 21 and 23 tighten around the pinion sprocket wheel 25 to a degree that the pinion sprocket wheel turns with the pinion shaft 15. During this cranking motion the ratchet and pawl 18 and 19 cooperate to prevent counterclockwise rotation of pinion shaft 15. The clockwise rotation of pinion sprocket wheel 25 is transmitted to the second sprocket wheel 33 through the chain 35. Since the sprocket wheel 33 is fixedly secured to the second shaft 28, this motion will thereby cause shaft 28 to rotate in a clockwise direction. During the clockwise rotary motion of the second shaft, the second ratchet and pawl arrangement 30 and 31 is operative to prevent counterclockwise rotation of said second shaft. The clockwise rotary motion of the drum 34, secured to the second shaft, causes the cable 36 to be wound upon said drum and thereby causes the boom 8 to be pivoted on the base 7 of the derrick. As seen in FIGURE 1, the pivotal movement of the boom towards a vertical position will cause the farm elevator to be raised.

If it is now desired to lower the upper end of the farm elevator the pawl 31 must be raised to the vertical position (as shown in broken lines in FIGURE 3) such that the second shaft 28 is free to rotate in a counterclockwise direction. The weight of the boom and the elevator will now tend to lower the elevator. However, since the second shaft 28 is secured to the pinion shaft through the chain 35 and the pinion shaft is prevented from rotating in a counterclockwise direction by the ratchet and pawl arrangement 18 and 19, the elevator will not yet move down. Upon turning the crank 27 in a counterclockwise direction the nut 26 is backed away from the stationary clutch plate 21 and thereby allows relative motion between the pinion sprocket wheel 25 and the pinion shaft 15, thus allowing the elevator to be lowered. The clutch plates which are controlled by the crank can be manipulated such that the elevator can be lowered at any speed desired and the downward movement can be stopped at any point. Since the crank 27 does not rotate when the elevator is being lowered, the crank can be grasped by the operator regardless of the speed the elevator is falling, and the downward movement of the elevator can be arrested.

From the above description it can be seen that a new and improved winch has been provided which is particularly adaptable for use with a derrick. This winch will allow a controlled unwinding of a cable regardless of the amount of pull or tension on the cable.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood, that within the scope of the appended claims, the invention may be practiced otherwise than is specifically described.

What is claimed is:

1. In a winch operated derrick adapted for use with a farm elevator, said derrick having a wheeled base and a boom pivotally mounted thereon, a winch mounted on said derrick comprising a support, a first shaft rotatably mounted on said support, means preventing rotation of said first shaft in one direction, a pinion sprocket wheel supported on and rotatable with respect to said first shaft, drive and brake means supported on said first shaft for rotating said first shaft and pinion sprocket in one direction and applying a braking pressure on said pinion sprocket when it attempts to rotate in the opposite direction, a second shaft mounted on said support and driven by said pinion sprocket wheel, ratchet means for preventing rotation of said second shaft in one direction, said ratchet means being disengageable such that in the inoperative position said second shaft is free to rotate in either direction, and a cable secured to said second shaft and to the free end of said boom.

2. In a winch operated derrick adapted for use with a farm elevator, said derrick having a wheeled base and a boom pivotally mounted thereon, a winch mounted on said derrick comprising a support, a pinion shaft rotatably mounted on said support, means for preventing rotation of said pinion shaft in one direction, a stationary clutch plate afiixed to said pinion shaft, a movable clutch plate rotatably carried by said pinion shaft, a pinion sprocket wheel carried by and rotatable with respect to said pinion shaft between said clutch plates, the outer end of said pinion shaft being threaded, an internally threaded nut having a crank secured thereto and adapted to be carried by the threaded end of said pivot shaft and to clamp said pinion sprocket wheel between the clutch plates when said crank is tightened, a second shaft rotatably mounted on said support, driven by said pinion sprocket and haying a second ratchet and sprocket wheel secured thereto, a second pawl pivotally mounted on said support and adapted to normally engage said second ratchet and prevent rotation of said second shaft in one direction, said second pawl allowing the second shaft to rotate in either direction when it has been mnaually pivoted out of its normal operative position, and a cable secured to said second shaft and to the free end of said boom.

3. A winch comprising a support, a first shaft rotatably mounted on said support, means preventing rotation of said first shaft in one direction, a pinion sprocket wheel supported on and rotatable with respect to said first shaft, drive and brake means supported on said first shaft for rotating said first shaft and pinion sprocket in one direction and applying a braking pressure on said pinion sprocket when it attempts to rotate in the opposite direction, a second shaft mounted and supported on said support and driven by said pinion sprocket wheel, ratchet means for preventing rotation of said second shaft in one direction, said ratchet means being disengagable such that in an inoperative position said second shaft is free to rotate in either direction.

4. A winch comprising a support, a pinion shaft rotatably mounted on said support means, for preventing rotation of said pinion shaft in one direction, a stationary clutch plate affixed to said pinion shaft, a movable clutch plate rotatably carried by said pinion shaft, a pinion sprocket wheel carried by and rotatable with respect to said pinion shaft between said clutch plates, the outer end of said pinion shaft being threaded, an internally threaded nut having a crank secured thereto and adapted to be carried by the threaded end of said pinion shaft and to clamp said pinion sprocket wheel between the clutch plates when said crank is tightened, a second shaft rotatably mounted on said support and having a second ratchet and sprocket wheel secured thereto, a flexible connection means for transmitting rotary motion from said pinion sprocket wheel to said second sprocket wheel, a second pawl pivotally mounted on said support and adapted to normally engage said second ratchet and prevent rotation of said second shaft in one direction, said second pawl allowing the second shaft to rotate in either direction when it has been manually pivoted out of its normal operative position.

References Cited by the Examiner UNITED STATES PATENTS 1,028,770 6/12 Moser 254 187 1,630,800. 5/27 Page 254166 X 7 2,009,356 7/35 De Seversky.

2,607,560 8/52 Bugg.

2,670,065 2/54 Stevens 192-18 2,756,947 7/56 Arnold.

2,899,840 8/59 Reeser.

SAMUEL F. COLEMAN, Primary Examiner.

HARRISON R. MOSELEY, ERNEST A. FALLER,

Examiners. 

3. A WINCH COMPRISING A SUPPORT, A FIRST SHAFT ROTATABLY MOUNTED ON SAID SUPPORT, MEANS PREVENTING ROTATION OF SAID FIRST SHAFT IN ONE DIRECTION, A PINION SPROCKET WHEEL SUPPORTED ON AND ROTATABLE WITH RESPECT TO SAID FIRST SHAFT, DRIVE AND BRAKE MEANS SUPPORTED ON SAID FIRST SHAFT FOR ROTATING SAID FIRST SHAFT AND PINION SPROCKET IN ONE DIRECTION AND APPLYING A BRAKING PRESSURE ON SAID PINION SPROCKET WHEN IT ATTEMPTS TO ROTATE IN THE OPPOSITE DIRECTION, A SECOND SHAFT MOUNTED AND SUPPORTED ON SAID SUPPORT AND DRIVEN BY SAID PINION SPROCKET WHEEL, RATCHET MEANS FOR PREVENTING ROTATION OF SAID SECOND SHAFT IN ONE DIRECTION, SAID RATCHET MEANS BEING DISENGAGABLE SUCH THAT IN AN INOPERATIVE POSITION SAID SECOND SHAFT IS FREE TO ROTATE IN EITHER DIRECTION. 